diff -urpN busybox-1.16.0/networking/udhcp/dhcpd.c busybox-1.16.0-dhcpd/networking/udhcp/dhcpd.c
--- busybox-1.16.0/networking/udhcp/dhcpd.c	2010-01-25 01:59:38.000000000 +0100
+++ busybox-1.16.0-dhcpd/networking/udhcp/dhcpd.c	2010-03-27 20:07:58.000000000 +0100
@@ -61,7 +61,7 @@ int udhcpd_main(int argc UNUSED_PARAM, c
 		logmode |= LOGMODE_SYSLOG;
 	}
 #if ENABLE_FEATURE_UDHCP_PORT
-	if (opt & 4) { /* -P */
+	if (opt & 8) { /* -P */
 		SERVER_PORT = xatou16(str_P);
 		CLIENT_PORT = SERVER_PORT + 1;
 	}
